Strategies to Improve Luminescence Efficiency and Stability of Blue Perovskite Light-Emitting Devices

Metal halide perovskite materials hold great potential as a core element in full-color display and lighting applications due to their unique optoelectronic properties, such as high photoluminescence efficiency, good color purity, tunable bandgap, and low-temperature solution processability. However, the performance of blue perovskite light-emitting diodes (PeLEDs) lags far behind their red and green counterparts, impeding their practical use. Herein, the recent progress on blue PeLEDs based on different restrictions and some feasible strategies to improve luminescence efficiency and stability are summarized. The methods to optimize blue-emission perovskite materials with different dimensions are addressed. The major factors affecting luminescence stability, the approaches to balance charge injection and minimize the optical loss are also discussed. Several problems in blue PeLEDs, particularly the toxicity of lead-based perovskites and the alternative solutions of lead-free perovskites, are emphasized. Finally, the perspective of future development in blue PeLEDs is provided.